Hi

I have a 2000 Mazda Millenia S (millenium ed), Miller Cycle Engine. It has 100K miles in it and runs OK. But with some problems..

1. At start-up, a bunch of smoke comes out of the exhaust. Is it NORMAL?

2. The car is running out of engine oil. I checked for leaks, can't find one. My garage floor stays clean. Every 500K I need to put in a bottle of engine oil (approx. 900ml)

3. My check engine light came on, and I took it to the dealer and the diagonistic showed that one of the CAT. converter is operating under threshold. I reset it, and the light hasn't came back on for the last one month.

That's all for now.

Thank you for your time.

-Raquib

 

I think your question #2 may be answering the others. If no external oil leaks are found and yet you are having to add a qt every 500 miles then it must be going thru the engine and being burned which would explain the smoke on start-up. A small amount of smoke is not considered normal but should be fairly light. If you notice it from inside the car then it is probably excessive. The Lysholm compressor is probably the source of the oil consumption as many Millenia S owner can attest to. The internal seals break down and draw oil into the intake air mixture is usual problem. There is an inspection port on the top that can be used to see if any oil is is the compressor where it should not be. This also may be contributing to the catalyst efficiency as the burned oil is very hard on converters. Have the front bank spark plugs removed to check for signs of oil consumption and that may provide the quickest answer. Point about the cat efficiency as well. There is a TSB from Mazda relating to overly sensitive rear oxygen sensors causing a Cat efficiency code but given the mileage and possible oil consumption problem I doubt it would apply in this case.

 

Thank you babyhuey

Any advice on what I can do to fix it? An economy sloution (if possible) would be nice. Will it be worse if i ignore this problem for now?

ps: I changed the spark plugs a month ago. The auto technicians did not mention anything going wrong with the plugs though.

Thanks again.

-Raquib.

 

raquib, no advise that I can give to fix unless you know what is the real problem. If the compressor is the problem then will be an expensive fix as the only repair is to replace and it is not inexpensive by any means. That may not be the problem but is the most common concern with this engine. I see that technicians changed the plugs a month ago but if they were not looking for a problem they may have just pulled and replaced without analyzing the condition of the plugs. An obvious problem should have been noted but that is not always the case if tech is just doing a service to replace and not paying attention to inspection of parts removed. Will it be worse? The only thing you will continue to damage if you are burning oil is the catalytic converters and they are not inexpensive either. Bottom line is that we need to determine where the oil is going and what repair is needed to eliminate the problems.